1. Field of the Invention
The invention relates to a transistor oscillator for the microwave frequency range embodied as a Clapp oscillator circuit which is a capacitive three-point circuit with a capacitance arranged in series with the circuit inductance.
2. Description of the Prior Art
Of the oscillator circuits customarily used in the microwave art, the Clapp oscillator offers the best possibilities for wide-band frequency tuning since the circuit inductance can be compensated by the reactive impedance of the capacitance. The highest oscillating frequency is obtained from the value of the collector-base capacitance and the smallest circuit inductance. The feedback network consists of capacitive voltage divider between collector and emitter and emitter and base, for which the parasitic collector-emitter and enitter-base capacitances can be used at higher frequencies. The influence of parasitic elements which usually exist in microwave oscillators impairs the wide band behaviour and gives rise to the occurrence of frequency jumping or instability.